Apparatus for heating gases



May 19, 1964 R. D. REED APPARATUS FOR HEATING GASES Filed July 17, 1961ROBERT D. REED ATTORNEY United States Patent 3,133,731 APPARATUS FURHEATING GASES Robert D. Reed, Tulsa, Gilda assignor to John Zmk Company,Tulsa, Okla a corporation of Delaware Filed Juiy 17, 1961, Ser. No.124,540 3 Claims. (Q1. 263-19) The present invention relates toapparatus for heating gaseous fluids and more specifically pertains tomeans 1n association with a fuel burner guiding a gaseous medium intoheat transfer relationship and into substantially intimate contact withthe heat produced by the burning fuel.

In the chemical, petroleum and process industries it is often necessaryto elevate the temperature of a gaseous medium which may benon-combustible or partially combustible in the presence of oxygen. Itis often desirable that the combustible elements of the gaseous mediumbe heated to develop exothermic oxidation of the combustible componentsfor the recovery of heat. In other instances it is desirable to heat anon-combustible gaseous medium which in turn serves to deliver heat toother areas. Apparatus is known which provides for the indirect heatingor firing of such gaseous fluids but such equipment is complex andcostly and the present invention is directed to apparatus for moving agaseous medium to be heated into the presence of a flame produced by afuel burner so that the heat developed by the burning fuel istransferred to the gas the instant that the fuel is burned and there isno delay in contact of the heat developed by the burning fuel with thegaseous medium.

An object of the invention is to provide casing means in associationwith a fuel burner for delivering a gaseous medium into the presence ofthe burning fuel in a zone where the combustion of the fuel is virtuallycomplete with the gaseous medium delivered into a zone at the downstreamend of the flame produced by the burning fuel thereby providingapparatus for heating large volumes of gases and with the heat delivereduniformly throughout the mass of the gaseous medium and without thenecessity of accessory devices for recycling the gaseous medium into thepresence of the heat source.

Another object of the invention is to provide apparatus for continuouslyheating a moving gaseous medium and to uniformly heat the gaseousmaterial without the necessity of providing supplemental means forforcing contact of the hot gases produced by burning fuel with thegaseous medium to be heated.

A further object of the invention is to provide a fuel burner whereinthe flame and the heat pattern of the burning fuel has an annular shapeand with casing means forming an annular passageway delivering thegaseous fluid as an annular stream transversely of the perimeter of theburning fuel and into intimate contact with the heat at the perimeter ofthe heat pattern.

Other objects and features of the invention will be appreciated by thoseskilled in the art to which the invention pertains as the presentdisclosure proceeds and upon consideration of the annexed drawing andthe following detailed description wherein one embodiment of theinvention is disclosed.

In the drawing:

FIG. 1 is an axial sectional view of apparatus exhibiting the invention.

FIG. 2 is an elevational view of the downstream end of the apparatus andshowing a fragmentary portion of a wall supporting the apparatus.

FIG. 3 is an elevational view of the rear end of the apparatus.

The invention is directed to means in association with a fuel burner forheating a gaseous medium and in a continuous manner as the gaseous fluidflows in the presence of the burner head. In the embodiment illustratedice in the drawing the assembly is supported on a wall 10 of arefractory type which also serves the purpose of providing a barrier sothat a pressure differential may be maintained on opposite sides of thewall. A pressure below atmospheric may thus be established beyond thedownstream face 11 of the wall 10. A relatively large cylindricalopening 12 is provided in the wall 10 for accommodating a generallycylindrical shaped casing 14. The free end of the casing 14 mayterminate flush with the downstream face 11 of the wall 10 and may beanchored to the wall in any suitable manner.

A ring-shaped tile member 16 formed of refractory material is arrangedwithin the opening 12. The tile member is partially encased by a sleeve17 of cylindrical shape having a smaller diameter than the interior ofthe casing 14. An annular passage 18 is thereby provided between theperimeter of the sleeve 17 and the interior of the casing 14. Thedownstream end of the tile member 16 is arcuate shaped as indicated at19 to provide an outwardly flaring profile in section at the exit end ofthe tile member 16. The remaining inner portion of the tile member 16has a cylindrical interior surface 21.

A tubular element 22 having an internal diameter substantially equal tothe diameter of the surface portion 21 of the tile member 16 carries aflange 23 at the upstream end thereof which is joined to the upstreamend of the casing 14 in any suitable manner such as by means of a boltand nut assemblies 24. The sleeve 17 encasing the tile member is joinedto the tubular element 22 by means of a flange 26. The structure may bereinforced to provide additional support for the tile member 16 by meansof a plurality of lugs one of which is shown at 27 in FIG. 1. The lugs27 are circumferentially spaced about the perimeter of the assembly. Thefree end of each lug 27 is in abutting relationship with the interior ofthe casing 14 and the inner end of the lugs may be welded to the tubularelement 22 and to the flange 26 as indicated in FIG. 1.

The casing 14 and the tubular element 22 and the parts associatedtherewith provide a chamber 28 which is in communication with theannular passage 18. The casing 14 carries a radially disposed conduit 29for connection to a source of the gaseous medium which is to undergoheat treatment. The gaseous medium enters the annular space 28 and movesthrough the passage 18 by reason of the fact that the pressuredownstream of the wall 10 is lower than atmospheric. If necessary meansmay be provided for forcing the gaseous medium through the annularpassage 18. It is desirable that the gaseous medium move through theannular passage 18 at fifty feet or more per second.

The open area provided interiorly of the tubular element 22 providesspace for accommodating a burner head and for the flow of secondary air.The burner may be of any suitable type but desirably produces a flamehaving an annular shape or pattern. In the embodh'nent illustrated inthe drawing a guide tube 31 extends coaxially of the tubular element 22.The downstream end of the guide tube 31 carries a frusto-conical shield32. The guide tube 31 is supported by a disc-shaped member 33 which issecured to the flange 23 in a conventional manner by means of a thimble34. Cap screws 36 and spacer elements 37 serve to support thedisc-shaped member in spaced relationship with respect to the upstreamend of the thimble 34. The thimble 34 is secured to the flange 23 bymeans of cap screws 38. An annular conduit 41 for the gaseous fuel ismounted within the guide tube 31 lad it is supplied with gaseous fuelthrough the fitting 42. The annular burner head 43 for the gaseous fuelis provided with a plurality of discharge ports 44 which have their axesso disposed as to provide an annular flame of substantiallyfrusto-conical shape as represented at 46.

If desired the burner may be of the type for the combustion of liquidfuel and such a burner includes a pipe 47 arranged inside the conduit 41and provided with a nozzle 4-8. The liquid is supplied through an inletfitting 51 on the tube 4-7. The nozzle 48 is provided with ports whichfunction to discharge the atomized liquid to provide a flame having anannular shape or frusto-conical pattern somewhat like that representedat 46. If desired both burners may be operated simultaneously.

An air control door structure 53 is provided for controlling the volumeof air admitted into an annular space 54 provided around the guide tube31. The door structure 53 is adapted to slide on the guide tube 31 andmay be moved by means of handles 56. It is desirable that the air moveat a velocity of at least fifty feet per second so as to provide forextremely rapid burning of the fuel. The fuels are delivered to therespective burner heads at a velocity between six hundred and threethousand feet per second. The fuel streams accordingly move at very highvelocity and carry huge quantities of energy. The air moving in theannular space 54 is at low velocity and accordingly carries very littleenergy. The high velocity fuel streams issuing from the respectiveburner ports set up low pressure zones at the points of discharge. Thusthere is extremely rapid mixing of the fuel with the air and extremelyrapid burning of the fuel. The fuel is virtually burned by the time itarrives adjacent of the drownstream end of the annular passage 18.

There is no mixing of the gaseous medium moving in the annular passage18 with either type of fuel nor is there any mixture of the gaseousmedium flowing through the annular passage 18 with the air for the fuelburners prior to the arrival of the gaseous medium at the exit end ofthe annular passage 18. The gaseous medium escaping through the exit endof the passage 18 and moving at a velocity of at least fifty feet persecond is instantly and evenly mixed with the hot gases produced by theburning fuel. It is this even and instant mixture of the heat with thegaseous fluid which produces an even temperature throughout the gaseousmass. Such an assembly contributes to a reduction of the space foraccommodating a large volume of the gaseous material undergoing heattreatment. The high velocities of the fuel streams provides rapidmixture of the fuel and air and high inertia for the fuel mixture whichsupplies energy for mixture with the gaseous fluid.

In the event that the gaseous medium is an inert gas the quantity of airadmitted to the presence of the burning fuel is limited by moving theair door structure 53 towards the closed position so that the airadmitted is limited to that required for burning the fuel. If thegaseous medium flowing through the passage 18 carries combustibleelements the quantity of air admitted to the presence of the burner headis increased by shifting the door structure 53 towards a more openposition so that the air entering the annular space 54 is thensuflicient for burning the fuel plus that required for burning thecombustible elements of the gaseous medium. As a consequence of the highenergy of the fuel streams the air is entrained with the fuel streamsfor instant delivery to the combustible elements if they are carried bythe gaseous medium flowing through the annular passage 18. Thetemperature of the gaseous medium is elevated to a point above thekindling temperature of the combustibles.

While the invention has been described with reference to one generalorganization including burner heads of a particular type it will beappreciated that changes may be made in the overall assembly along withchanges in the various elements. Such modifications and others may bemade without departing from the spirit and scope of the invention as setforth in the appended claims.

What I claim and desire to secure by Letters Patent is:

1. Apparatus for heating a gaseous fluid comprising, a wall having adownstream face and an exterior face, said wall having a circularopening therethrough, a cylindrical shaped casing fitting within saidopening and extending from the exterior face of said wall, a tubularelement of smaller diameter than said casing arranged substantiallyconcentrically therewithin, a sleeve carried by said tubular elementwithin said casing having an end within said opening and forming anannular passage between the casing and the sleeve, a ring shaped tilemember fitting within said sleeve and having an inner annular surfacesubstantially flush with an inner annular surface of said tubularelement, means spaced from said exterior face joining the casing withthe tubular element providing a close annular chamber, means for guidinga gaseous fluid into said annular chamber for movement through saidannular passage for discharge as an annular stream from the downstreamface of said wall, a tube of smaller diameter than said tubular elementarranged substantially concentrically therein, a fuel burner headsupported by said tube within the opening in said wall, means forsupplying fuel to said burner head, said tubular element and said tubeforming an annular passage therebetween for movement of air into thepresence of the burner head, and said burner head having discharge portsproviding an annular pattern of burning fuel extending generallyradially from the burner head to heat the gaseous fluid as it isdischarged from said annular passage.

2. Apparatus for heating a gaseous fluid according to claim 1 wherein,an annular flange extends from the sleeve to the tubular element andcovers an inner end of the tile member.

3. Apparatus for heating gaseous fluid according to claim 1 wherein, thedownstream end of the tile member flares outwardly in proceeding fromits inner annular surface.

References Cited in the file of this patent UNITED STATES PATENTS1,710,900 Schilling et al. Apr. 30, 1929 2,144,098 Baker Jan. 17, 19392,485,656 Raskin Oct. 25, 1949 2,583,736 Hess Jan. 29, 1952 2,840,152Reed June 24, 1958 3,049,173 Costello et al Aug. 14, 1962

1. APPARATUS FOR HEATING A GASEOUS FLUID COMPRISING, A WALL HAVING ADOWNSTREAM FACE AND AN EXTERIOR FACE, SAID WALL HAVING A CIRCULAROPENING THERETHROUGH, A CYLINDRICAL SHAPED CASING FITTING WITHIN SAIDOPENING AND EXTENDING FROM THE EXTERIOR FACE OF SAID WALL, A TUBULARELEMENT OF SMALLER DIAMETER THAN SAID CASING ARRANGED SUBSTANTIALLYCONCENTRICALLY THEREWITHIN, A SLEEVE CARRIED BY SAID TUBULAR ELEMENTWITHIN SAID CASING HAVING AN END WITHIN SAID OPENING AND FORMING ANANNULAR PASSAGE BETWEEN THE CASING AND THE SLEEVE, A RING SHAPED TILEMEMBER FITTING WITHIN SAID SLEEVE AND HAVING AN INNER ANNULAR SURFACESUBSTANTIALLY FLUSH WITH AN INNER ANNULAR SURFACE OF SAID TUBULARELEMENT, MEANS SPACED FROM SAID EXTERIOR FACE JOINING THE CASING WITHTHE TUBULAR ELEMENT PROVIDING A CLOSE ANNULAR CHAMBER, MEANS FOR GUIDINGA GASEOUS FLUID INTO SAID ANNULAR CHAMBER FOR MOVEMENT THROUGH SAIDANNULAR PASSAGE FOR DISCHARGE AS AN ANNULAR STREAM FROM THE DOWNSTREAMFACE OF SAID WALL, A TUBE OF SMALLER DIAMETER THAN SAID TUBULAR ELEMENTARRANGED SUBSTANTIALLY CONCENTRICALLY THEREIN, A FUEL BURNER HEADSUPPORTED BY SAID TUBE WITHIN THE OPENING IN SAID WALL, MEANS FORSUPPLYING FUEL TO SAID BURNER HEAD, SAID TUBULAR ELEMENT AND SAID TUBEFORMING AN ANNULAR PASSAGE THEREBETWEEN FOR MOVEMENT OF AIR INTO THEPRESENCE OF THE BURNER HEAD, AND SAID BURNER HEAD HAVING DISCHARGE PORTSPROVIDING AN ANNULAR PATTERN OF BURNING FUEL EXTENDING GENERALLYRADIALLY FROM THE BURNER HEAD TO HEAT THE GASEOUS FLUID AS IT ISDISCHARGED FROM SAID ANNULAR PASSAGE.